Extending Sleep in Obese Adults to Promote Weight Loss

据估计，美国大约三分之二的成年人超重或肥胖。没有一个人口群体幸免于难；所有年龄段、性别和所有种族群体的肥胖率都有所增加。肥胖症急剧增加的原因包括越来越多的久坐不动的生活方式，以及食品生产和营销实践的变化，中央供暖和空调的使用增加，怀孕年龄增加，吸烟率下降，睡眠时间缩短。由于自愿减少睡眠而导致的睡眠不足在所有年龄段的美国人中都很常见。许多流行病学研究表明，睡眠时间减少和体重指数(BMI)增加之间存在剂量依赖关系。此外，控制良好的实验室研究证明，睡眠不足似乎通过改变代谢荷尔蒙准确发出热量需求信号的能力来上调食欲，改变葡萄糖代谢，增加胰岛素抵抗，并升高血压。有人建议--但从未被证实--延长睡眠时间将有助于减肥。因此，该项目的目标是为未来的临床试验奠定基础，以检验这一假设，即每晚睡眠至少7.5小时的健康肥胖者比每晚睡6.5小时的健康肥胖者减轻的体重更多。具体地说，该项目的目标包括：1)测试作为传统减肥计划辅助的延长睡眠方案的可行性；2)比较睡眠延长结合卡路里限制和锻炼与传统体重控制计划的效果，其中传统体重控制计划包括热量限制和运动，以促进肥胖者的减肥；3)比较睡眠延长方案与传统减肥计划的效果，其中传统减肥计划包括热量限制和锻炼，以使健康肥胖者的血糖水平和血压正常化；以及4)探索延长睡眠时间对瘦素和胃促生长素水平的影响。睡眠延长协议将利用与坦普尔大学肥胖研究和教育中心已经使用的行为修改协议相同的原则，例如，对行为进行渐进但可持续的改变，设定每周的行为目标，自我监控实现目标的进展，识别障碍等，并将被纳入每周的小组会议。

Approximately two-thirds of all adults in the United States are estimated to be overweight or obese. No demographic group has been spared; increased rates of obesity have been documented in all age groups, in both sexes, and among all ethnic groups. Explanations for the dramatic increase in obesity include increasingly sedentary lifestyles, and changes in food manufacturing and marketing practices, the increased use of central heating and air conditioning, increasing gravid age, decreased smoking rates, and decreased sleep durations. Sleep loss due to voluntary curtailment of sleep is common among Americans of all ages. Numerous epidemiologic studies have revealed a dose-dependant relationship between reduced sleep duration and increased body mass index (BMI). In addition, well-controlled laboratory studies have documented that sleep loss appears to up-regulate appetite by altering the ability of metabolic hormones to accurately signal caloric need, alters glucose metabolism and increases insulin resistance, and elevates blood pressure. It has been suggested--but never tested--that extending sleep will facilitate weight loss. Therefore, the goal is of this project is to lay the groundwork for a future clinical trial testing the hypothesis that healthy obese individuals who obtain at least 7.5 hours sleep per night will loose more weight than healthy obese adults obtaining 6.5 hours sleep per night. Specifically, the goals of this project include: 1) feasibility testing of a sleep extension protocol as an adjuvant to traditional weight loss programs; 2) comparing the efficacy of sleep extension in combination with caloric restriction and exercise to a traditional weight control program consisting of caloric restriction and exercise for facilitating weight loss in obese individuals; 3) comparing the efficacy of a sleep extension protocol in combination with caloric restriction and exercise to a traditional weight loss program consisting of caloric restriction and exercise to a traditional weight loss program consisting of caloric restriction and exercise for normalizing glucose levels and blood pressure in healthy obese individuals; and 4) explore the effect of sleep extension on leptin and ghrelin levels. The sleep extension protocol will utilize the same principles as the behavioral modification protocol already in use at Temple University's Center for Obesity Research and Education e.g., making incremental but sustainable changes in behavior, setting weekly behavioral goals, self-monitoring of progress towards goals, identification of barriers, etc., and will be incorporated into weekly group meetings.